Lens surfacing machine



March 25, 1947. D. E. MU-LHOLLAND ETAL 2,418,086

LENS SURFAGING MACHINE 1s Sheets-Sfieei 1 Filed May 15, 1945 Mara! 1947.D. E. MULHOLLAND ETAL 2,413,086

LENS SURFACING MACHINE Filed May 15, 1945 13 Sheets-sheaf 2 March 25,1947.

. D. E. MULHOLLAND ETAL 2,418,086

LENS SURFACING MACHINE Filed May 15, 1945 13 Sheets-Sheet 3 044 10 5.M04 #042. #N0, Gus 7794 F196 March 25, 19475 MULHOLLAND r AL 2,418,086

LENS SUBFACING MACHINE F iled May 15, 1945 13 SheetsSheet 4 March 1947-D. E. MULHOLLAND ETAL 2,418,036

was SURFACING MACHINE Filed May 15, 1945 13 Sheets-Sheet 5 -lvlzmrch 25, 1947- D. E. MULHOLLAND ETAL LENS SURFACING MACHINE Filed May 15, 194513 Sheets-Sheet 6 March 25, 1947.

D. E. MULHOLLAND ETAL 2,418,086-

LENS SURFACING MACHINE Filed May 15; 1945 13 Sheets-Sheec 7 Marcb 25,1947- DE. MULHOLLAND ETAL LENS SURFACING MACHINE Filed May 15, 1945 13Sheets-Sheet 8 I March 25', 1947. I D. E. MULHOLLAND ETAL 2,418,036

LENS SURFACING MACHINE Filed May 15, 1945 l3 Sheets-Sheet 9 I III March25, 1947. D. E.-MULHOLLAND ETAL 2,418,086

LENS SURFACING momma:

Filed. May 15, 1945 l3 Shets-Sheet 10 swam MS Mi ch 25, 1947. D. E.MULHOLLAND ETAL 2,418,036

LENS SURFACING MACHINE l3 Sheets-Sheet 11 Filed May 15, 1945 March 25,1947.

D. E. MULHOLLAND ETAL LENS SURFACING MACHINE Filed May 15, 1945 13Sheets-Sheet l2 swam W06 Marfih 1947- DE. MULHOLLAND ETAL 2,418,056

LENS S'URFACING MACHINE I 5 Fi led May 15, 1945 l3 Sheets-Sheet l3Patenied Mar. 25, 1947 LENS SURFACING MACHINE David E. Mulholland,Reading, Pa, Gustave Fast, Salisbury, Md, and Kirk S. Lawrence, WestReading, Pa.

Application May 15, 1945, Serial No. 593,850

28 Claims.

This invention relates to grinding or polishing machines and moreparticularly to machines for rinding or surfacing lens blanks with acurved surface.

A principal object of the invention is to provide improved means forrotating a lens blank spindle and for simultaneously moving a member inwhich the spindle is mounted to and fro in a curved path to cause thelens blank to move in such a path.

Aprimary feature of the invention consists in providing hydraulic means,such as an oil gear motor for rotating the lens supporting spindle as itis moved to and fro in a curved path.

Another feature of the invention consists in providing an oil gear motorfor rotatin the spindle having means whereby a part of the oil fordriving the motor is employed to lubricate bearings for the spindle.

A further feature of the invention consists in providing a rectilinearlymovable slide which is flexibly connected to the lens holding means sothat reciprocation of the slide will cause the lens holding means tomove to and fro in a curved,

path.

A still further feature of the invention consists in providing an apronor flexible shield which is successively wound and unwound on spacedrollers during movement of the lens holding means so as to protect thebearings of the spindle from material incident to the grindingoperation.

Other and more specific features of the invention, residing inadvantageous forms, combinations and relations of parts, willhereinafter appear and be pointed out in the claims.

In the drawings,

Figure l is a side elevational view of a machine embodying theinvention.

Figure 2 is a plan View of the machine illustrated in Figure 1.

Figure 3 is an enlarged vertical sectional view of the right end portionof the machine.

Figure l is an enlarged vertical sectional view taken longitudinally ofthe pivoted beam adjacent the lens supporting spindle.

Figure 5 is a fragmentary transverse sectional view taken on line 55 ofFigure 3.

Figure 6 is a fragmentary vertical sectional view taken on line t% ofFigure 2.

Figure 7 is a fragmentary horizontal sectional View taken on line 7-7 ofFigure 1.

Figures 8 and 9 are plan and side views respectively of therectilinearly movable slide.

Figure 10 is an end view of the slide.

Figure 11 is a detail sectional view on line I i-! l of Figure 8.

Figures 12 and 13 are horizontal sectional views taken on lines i2-i2and l3-13, respectively, of Figure 4.

Figure. 14 is a sectional view on line l4l4 of Figure 13, the upper partof the structure being omitted.

Figure 15 i an enlarged fragmentary sectional view of portions of thecoacting gear wheels, the view being taken in the plane of radialopenings in one of the wheels.

Figure 16 is an enlarged vertical sectionalview of the lower spindlebearing.

Figure 17 is a bottom view of the bearing in Figure 16.

Figure 18 is a plan view of the lower gear sleeve bearing. Figure 1 9 isa, sectional view taken on line til-49 of Figure 18.

Figure 20 is a side view of a cast ironblock which, after being cut intwo, forms opposed way blocks for side 'wall portions of the beam.

Figure 21 is a fragmentary sectional viewtaken onlineEI-EiofFigureZO.Figure 22 is a plan view of the upper spindle bearing. r Figure 23 is asectional view taken on line 23-43 of Figure 22.

Figure 24 is a fragmentary sectional view taken on line 24-24 of Figure22.

Figure 25 is a fragmentary sectional view taken on line 25-25 of Figure22.

Figure 26 is a plan view of the pin or fulcrum on which the idler'gearwheel of the'gear motor is rotatably mounted.

Figure 27 is a side elevational View of the pin or post of Figure 26.Figure 28 is an enlarged fragmentary View of the spindle and adjacentparts.

" Figure 29 is a front side view of the construction illustrated inFigure 28.

Figure 30 is a plan view of a portion of the spindleair seal ring,

Figure 31 is a transverse vertical sectional view of the ring.

Figure 32 is a plan view of a dle pump ring.

Figure 33 is a side elevational view of a portion of the pump ring.

portion of the spin- Figure 34 is an enlarged detailed sectional View Qshowing the profile of the lower edge of the pump ring.

The present invention is particularly'designed for use in a pivoted beamI of the character fully described and claimed in the copending patentapplication of Mulholland and Lawrence, Serial Nb. 488,256, filed May24, 1943, with which a relatively stationary rotatable surfacing meniberof the character there shown or of any other similar character may beassociated.

The beam may/in the main, be formed'as a single unitary casting havingside walls 2 and a top wall 3. At the end nearest the surfacing means,the beam is preferably provided with suitable hydraulic mechanismwhereby it can be selectively caused to move toward and away from thesurfacing means. The hydraulic mechanism may be ofthe same character asthat illustrated in said copending application where the beam is formedwith a downwardly extending yoke 4 having oppositely projecting posts 5which are respectively adapted to cooperate with diaphragms 6 mountedwithin opposed cylinders land 8. The beam is preferably maintained in acondition of balance and it will, therefore, immediately respond tochanges in forces to which it is subjected by the hydraulic means or anyother means.

Downward pivotal movement of the beam is preferably limited by anadjustable stop consisting of a rod 9 which is screw threaded in the hub'of a rotatable hand wheel Ii] suitably journaled in brackets .Ilsecured to the end wall of thebeam, the lower end of the stop rod beingengageable with a part l2 rigid with the base ofthe machine.

' ..As in th copending application referred to,

upward pivotal movement of the beam by the hydraulic mechanismmayconsist of an inverted yoke or U-shaped member 13 rigid with the basewhich straddles a yoke or U-member it rigid with the beam, the yoke I3being provided with a vertically adjustable screw threaded memher [5.This member may be conveniently rotated through any suitable means by ashaft lfiIwhich extends through an elongated slot in one of the legs orarms of the yoke I l and the lower. end of the screw threaded member isadapted to be engageable with the bottom or web portlon of .the yoke it.Thus an adjustable stop is provided which acts in opposition to thehydraulicv means for pivoting the beam upwardly whereby the amount ofmaterial removed from the faceof-the work being surfaced by thesurfacing means may be accurately controlled.

The bearings I! which afford the pivotal sup port for the beam arevertically adjustable in upright standards l8 so that at the conclusionof the'surfa'cing'operation the beam will be in a predetermined angularposition with reference to the vertical. The vertical adjustment of thebearings may be conveniently obtained, as in said pending application,by providing upwardly extending rotatable rods [9 which are screwthreadedwithin depending portions 20 of the bearings, adapted to berotated by a motor 2|, for example. i

Extending upwardly from adjacent that part of the beam above theadjustable stop member l5 are side wall portions 22 having curvedgrooves 23in their inner faces affording guideways in which the lensholding means is movable back and forth so as to cause a lens blankmounted thereon to move in a curved path. The side wall 'portions eachconsist of a plate-like way block 24 whose. upper inner edge has arecess 25 and a-cur'ved retaining member 26 which is removably securedto the upper edge of the way block 'bybolts or the like 21 so as to formthe grooves member to thus provide wall portions having concentric.recesses. .The curved retaining members 26 maybe similarly formed byfirst machining a ring to the desired dimensions and then cutting itinhalf so as to provide two members.

The means for holding a lens blank consists, in the main. of a bodyelement 29, a rotatable spindle 30 which is journaled in the body, andan oil gearmotor 3| for rotating the spindle. The body element includesan upper member 32-, which may be termed a spindle way block, havingcurved ribs or rings removably connected thereto at opposite sidesextending into the guideways 23 to afford a slidable support for theentire lens holding means. One of the ribs may be. in the form of a ring33a and may be con-. veniently marked on its outer side in degreessothat movement of the lens holding meansin degrees may be easily noted.The other rib 33b on the opposite side of the way block is pref--verably not in the form of a ring but instead may be only a segment of aring so that the lens surfacing means shown in Figure 2 and designated Amay be mounted adjacent that side of the beam and extend over the topthereof to operatively cooperate with a lens blank mounted on the spin-.dle and not interfere with free pivotal movement of the beam.

Secured to the under side of the spindle way block by bolts 34 or thelike and forming apart ofthe body element of the lens holding means are.plate members 35 and 35 respectively forming the top and bottom platesof an oil gear motor which involves two gear wheels 38. The sides of theoil gear motor are formed by a plate 39 which is clamped between the topand bottom gear plates and rigidly connected to the under side of thebottom plate 36 is a member 46 for housing the lower end of the spindle353. For con venience, this member may be formed in two complementaryparts which may be easily connected by bolts M or the like.

oil, or other fluid if desired, is supplied under pressure to the oilgear motor through a flexible conduit or pipe 42 which communicates atone end with a suitable supply pipe 43 and which at its other endcommunicates with a swivel connection 44 mounted on the lower end of thebody element 29 and having communication with a passageway 45 leadingupwardly to the gear motor. This passageway communicates with divergingpassages MB which direct the oil against the teeth of the gear wheels 38to cause the wheels to rotate in opposite directions. The passages t5are formed by mounting a substantially diamond-shaped plate 41 in one ofthe -V-shaped recesses in the intermediate gear plate 39.

One of the gear wheels is keyed to a sleeve 43 which is splined, asindicated at 49, to the spindle 30 so that, as the gear wheels areforced to rotate in opposite directions by the fluid supplied thereto,the spindle is caused to rotate.

As the flexible oil supply pipe 42 is secured to the swivel connection44, the lower end of the body is free to move back and forthin a curved,path between the two dot and dash line positions indicated in Figure 6.To take up the slack which occursin the flexible conduit as the bodymoves to and fro and yet to permit that movement to be unhampered, theconduit may advantageously be supported on a roller carried on a shaft5| supported at its opposite ends in lugs 52 extending downwardly from ahorizontal plate 53 rigidly connected to the top wall of the beam.

Betweenthe roller 50 and the point at which the conduit is connected tothe main supply pipe, the conduit is provided with a weight 54 to takeup the slack. Adjacent the swivel connection 44, the flexible conduitmay also preferably pass beneath a roller carried on a shaft 5% mountedat its opposite ends in the side walls 2.

t is thus to be seen that oil under pressure may be supplied to the gearmotor without interfering with swinging movement of the body element inthe guideways in the side wall portions of the beam and that the motorwill operate continuously during sliding movement of the body in acurved path to eifectrotation of the spindle. To. insure perfectsphericity of the lens surface to begenerated, the axis about which thebody element swings :to and fro is intersected by the of rotation of thespindle.

To supply lubricant to the guideways, a pair of brackets 51 is mountedon opposite ends of each way block 2d on which gravity feed oilers 53are mounted, communicatingthrough passages 59 in the brackets with theinner end portions of the grooves 23. From there, the lubricant may passinto transversely extending grooves 56 in the top and bottom walls ofthe guideways, the transverse grooves in the bottom wall of theguideways being clearly seen in Figure 21.

Extreme precision is required in surfacing lens blanks and the rotatingspindle is, therefore, journaled so that it will not vibrate or wabblewithin the body 25. For this reason the'spindle is provided with spacedshoulders iii and 62,

respectively, and an intermediate downwardly tapering peripheral surface$3. The opening in the body in which the spindle is disposed hascorrespondingly shouldered portions and an intermediate bearing E ihaving a downwardly tapering inner surface 65 of the same inclination asthe tapered peripheral surface of the spindle. This bearing which ispreferably provided at its upper end with a laterally projectingcircular flange fit-underlying the upper shoulder 6| of the spindle isadvantageously formed with an outer steel shell portion 6'! and a liningof suitable bearing material 68. The upper surface of the top flange ofthe bearing is undercut, as indicated at E9 in Figure 24 and id inFigure 25, and the inner surface of the tapering portion thereof isundercut, as indicated at H in Figure 23, so that the bearing materialwhich is applied to the shell in. a molten state may flow intotheseparts and be firmly interlocked therewith. The outer surface of thebearing shell is cylindrical in part, as indicated at 12, so as to beheld firmly within a corresponding cylindrical opening in the body and,in addition, portions of its outer surface incline inwardly anddownwardly, as indicated at it, to form spaces M between the bearing andthe body for receiving lubricant under pressure.

In the present embodiment of the invention, the bearing is shown asproviding three lubricant receiving spaces and each one of themcommunicates by a duct 15 with an annular groove 19 formed in the innerface of the bearing. The bearing is so positioned within the opening inthe body that one of the spaces is in direct communication with alubricant supplying groove 11, to be hereinafter described, formed inthe under side of the wayblock 32. The inner face of the bearing isprovided with a plurality of longitudinally extending grooves l8 whichcommunicate attheir lower ends with the annular groove 16 and the uppersurface of the flange 66 of the bearing is formed with aplurality ofradially disposed grooves 79 which form continuations of thelongitudinal grooves .78. It; is thus to be seen that, since the annulargroove i5 is in open communication with each of the lubricant spaces.14, the grooves 78 and 19 are likewise, at all times, in communicationwith all of the spaces. An ample supply of lubricant is, therefore,always available for the hearing.

The upper portion of the spindle is so formed that the lower shoulderedportion 62 is spaced from the body whereas the upper shouldered portion6! andthe downwardly inclined peripheral surface thereof are inengagement with the hearing es. When lubricant is supplied underpressure to the grooves on the inner face of the bearing, as hereinafterpointed out, athin film of oil is always maintained between the coastingsurfaces of the spindle and bearing so that the spindle, in effect,floats on oil.

Oil under pressure is supplied to the bearing 34 by providing the secondgear wheel 38, the idler gear wheel, with a plurality of radiallyextending passages :89 whose outer ends terminate in the inner walls 8!of the spaces between the teeth of the gear. The gear is rotatablymounted on a fulcrurnpin. or post 82 which is keyed, as indicated at'83, to the top mOtOr plate 35. The bushing 84 which is freely rotatableabout the pin is keyed to the idler gear and has radial passages 85 inalignment with the passages thereof.

The fulcrum pin has a longitudinally extending passage 86 whichcommunicates at its upper end with'the passage Tl, heretofore described,leading to one of the lubricant spaces 74. Adjacent its lower end, itis'formed with a radial passage 8? in the same plane asthe radialpassages 80 in the idler gear so that, as the idler gear rotates, theradial passages thereof successively communicate with the radial opening8? in the fulcrum pin and thus cause lubricant to enter the longitudinalpassageway of the pin.

In the operation of the oil gear motor, most of the oil supplied to thegear wheels is discharged fromthe motor on the side opposite of the oilinlet side, passing through an outlet passage 88 having communicationwith a separate passageway 89 in the swivel joint 44 to which anotherflexible pipe 99 identical with the sup ply pipe 42 is connected. Theoutlet pipe and the supply pipe are preferably connected by clips 9landmove together in unison.

Although the oil is discharged through passage 88, a thin coating orfilm-0f oil nevertheless remains on the teeth of the gear wheels and theteeth interlock so accurately that, as each tooth of the driving gearwheel extends into the space between the adjoining teeth of the idlergear wheel, a large part of the oil remaining on the teeth is forcedunder pressure through the radial passageways into the othercommunicating passages heretofore described to lubricate the bearmg.

Surrounding the sleeve 58 which, as previously described, is keyed toboth the driving gear wheel and to the stem portion of the spindle areupper and lower sleeve bearings 92 and 93, respectively. The lower endof the upper bearing is provided with a flange 94 overlyin the uppersurface of the driving gear wheel and the upper end of the lower sleevebearing is formed with a similar flange 95 underlying the bottom surfaceof that wheel. The flanges of both of these sleeves have grooves 96formed in their outer faces which communicate with longitudinallyextending grooves=91 in-the-inner faces of the bearings.

Thus oil which seeps from'the gear motor be tween the top andbottomfaces of the driving gear wheel will pass. into the grooves ofthesebearings and thus lubricate the stem portion of the spindle, that is,the outer surface of sleeve 48.

The spindle is secured within the body element against upwardlongitudinal displacement by a thrust collar 98 encircling the lower endof the stem portion, a locking ring 99, washer I and lock nuts IIlIbeing employed to secure the thrust collar in the desired position. Abearing I02 which'encircles the lower end of the spindle has a laterallyprojecting lower flange I03 interposed between the bottom gear plate 36of the body and the thrust collar whereby the bearing is rigidly clampedto the body.

The inner surface of the bearing Hi2 and the bottom surface of theflange I03 thereof are coated or lined, as indicated at I04, withsuitable bearing material. gear motor into the grooves in the upper andlower sleeve bearings 92 and 93 will seep downwardly into grooves IIMain the inner surface of the bearing and the bottom flange thereof tolubricate engaging portions of the bearing and spindle, as well asengaging portions of the bearing flange and the thrust collar 98. Thusan abundance of oil is always supplied between all relatively movingparts of the body and spindle. Excess oil passing downwardly may collectin a sump formed by the member 40 housing the lower end of the spindle.

The lens holding means, as a whole, is movable back and forth in thecurved guideways 23 by a rectilinearly movable reciprocating slide I35which advantageously consists of two side members Hit and two endmembers I01. The outer faces of the side members have convergingportions Hi8 to fit within and be slidably supported by V-shaped groovesin the inner faces of suitable members rigid with the side walls of thebeam as shown in dot and dash lines in Figure 5. Reciprocating movementis imparted to the slide by a rod Hi9 pivotally connected at one end bya pin Iii! to the forward portion of the slide and E f pivotallyconnected at its other end by a pin I I I to a rotating disk II2, asseen in Figure 7. The disk may be rotated in any convenient manner, suchas by a motor I I3.

The lens supporting means extends downwardly into the space between theside and end members of the slide and each end of the bodyelementthereofis connected to the opposite end of the slide by a pair offlexible metal bands, the pair of bands secured to the end of the slideadjacent the connecting rod II9 being designated by II4 and the pair ofbands connected to the other end of the slide being designated by H5.

The bands thus extend toward each other and, to prevent them fromfouling in moving the lens holding means, bands II lare connected tolugs I it which, as may be seen in Figure 8, are spaced a greaterdistance apart than a pair of lugs II? at the opposite end of the slideto which the bands Iiii are connected. The other ends of the bandsunderlie the curved under surface of the spindle way block it and theirend portions I I8 are pref-' erably clamped to the underside of the wayblock by removable plates I I9 and studs I20, which permit the bands tobe self-aligning. It will be observed that the bands extend downwardlyfrom the way block to their point of attachment to the horizontal slideand thus they always exert a downward pull on the block.

.Theends of the .bandssecured to. the slide I Oil which has passed fromthe oil adjacent faces of the lugs.

are each connected between spaced portions of a rod or clamp I2 I whichis adapted to be positioned within a U-shaped recess in the lug of theslide to which, the band is to be secured. The outer ends of the rodsI2I are screw threaded to receive lock nuts I22 for securing them to thelugs. Resilient or spring means is preferably employed in the connectionof the rods to the lugs so as to absorb some of the shock which isnaturally transmitted to the bands, and consequently to the lens holdingmeans,'each time the slide reverses its direction of movement, and forthis purpose a coil spring I23 is interposed between the lock nuts onthe ends of the rods and the Suitable spring caps I24 are'preferablyemployed at opposite ends of each coil spring.

When the slide IE5 is moved by the rod I09in one direction, one pair ofthe flexible bands causes the lens holding means to move generally inthe same direction, and when the slide is caused to move in the oppositedirection, as described, the other pair of bands causes the lens holdingmeans to also move in the opposite direction. However, since the lensholding means is supported by curved ribs which extend into thesimilarly curved guideways 23. it will travel in a curved path while theslide travels in a rectilinear path. This difference in character ofmovement of the two bodies is made possible by the flexible bandsconnecting them. Rotation of the spindle as the lens holding means movesto and fro in a curved path is, of course, not dependent upon thisconnection since the oil supplied to the oil gear motor within the lensholding means is fed thereto by a flexible pipe pivotally connecteddirectly to the holding means.

To prevent water and other material incident to the surfacing operation,such, for example, as loose particles of the surfacing means and par.-ticles of glass from the lens itself, from working down into the spindlebearings and also for preventing oil supplied to the bearings fromworking its way out around the top of the spindle, the spindle isprovided with an annular flange 25 at its upper end, and a seal I25 ismounted in the spindle way block 32 immediately below the flange I215encircling thecylindrical portion I21 of the spindle. An apron I28having an opening intermediate its ends of substantially the samediameter as the outer diameter of the seal I26 is rigidly clamped to theupper surface of the spindle way block by a clamp member I29 which, likethe apron, extends transversely of the spindle way block from one sidethereof to the other. The clamp encircles the seal and, as seen inFigure 5, has portions which extend beneath it at diameterically opposedpoints in alignment with the axis of curvature of the upper surface ofthe way block. While the under surface of the apron clamp is curved andconforms to the upper surface of the-spindle way block, its uppersurface is flat and is disposed in a plane slightly below the under sideof the peripheral flange I25. Bolts I133 may be conveniently employedfor connecting the clamp to the spindle way block.

The ends of the apron I28 are respectively secured to rollers RSI whichmay be conveniently mounted on the brackets 5! on the upper end portionsof the circular way blocks or wall portions 2 8. Rigid with one end ofeach roller is a sheave I32 around which one end of a wire cable or thelike I33 may be wound. The wire cable of each sheave extends downwardlyon the outside of the adjacent wall; of the beam and may be secured by atension spring indicatedv in dot and dash lines. As seen in Figure 3,the wire cables I33 are connected to the sheaves in such manner that thetension of the springs to which they are respectively secured will causethe rollers I3I to rotate in opposite directions. The two ends of theapron I28 are oppositely wound upon the rollers I SI so that the pull ofthe spring connected to one of the wire cables I33 acts in opposition tothe pull of the spring connected to the other wire cable. Thus therollers maintain the apron in tension and as the lens surfacing meansmoves to and fro the apron is successively wound on one roller andunwound from the other.

Overlapping the upper face of the apron is a plate I35 having anopeningfor receiving the top flange I25 of the spindle which extendstransversely of the spindle way block from one side thereof to theother. The side edges of this plate are curved upwardly as indicated atI36 so as not to present sharp edges which would otherwise cut into theapron as the lens holding means moves back and forth.

In assembling the apron clamp I29 with the lens holding means, tapereddowels I3! are preferably employed and, should it be desired to renderthe oil gear motor inoperative and secure the spindle against rotationto the spindle way block, a bolt such as indicated in dot and dash linesat I38 may be employed.

The seal I 25 for preventing water and such material as abrasive grainsand particles of glass from the lens itself from working down into thespindle bearings as well as for preventing oil supplied to the bearingsfrom working its way out around the top of the spindle consists of apump ring I40 which is shrunk on to the upper portion of theoutersurface of the cylindrical part i2! of the spindle and anencircling air seal ring I 4| The pump ring is formed on its outer facewith inclined vanes or ribs I42 forming intervening grooves I43. Thelower edge of the ring is serrated or kerfed to provide surfaces I44which incline upwardly in the direction of rotation of the ring, theupper end of each inclined surface being connected to the lowest ortrailing end of the next preceding inclined surface by a substantiallyvertical wall portion or face I45. The ribs I42 extend upwardly at agreater angle to the horizontal than the inclined surfaces I44 and theyare preferably positioned with respect to them so that the upwardlyfacing side wall of each rib intersects the lowest point of a serrationand the downwardly facing side wall intersects the uppermost point ofthe next preceding serration, the downwardly facing side of the portionof the rib between these points being preferably in the same plane asthe adjacent inclined surface.

It will thus be seen that any oil which is forced upwardly by the actionof the oil gear motor heretofore described between the upper cylindricalportion of the spindle. and the way block 32 will, when the spindle isrotated, be engaged by the inclined surfaces I44 and thus be subjectedto downward pressure, overcoming the upward pressure imparted to it.

Such oil as might seep upwardly between the outer face of the pump ringand the air seal ring I45 will be subjected to a downward force by theribs I42.

The air seal ring I 4| may advantageously be made of bronze and is ofchannel-shape in cross section having a web I46 and inner and outerannular walls I41 and I48 respectively. The web 10 or bottom portion I46 of the channel rests in part on the circular way block 32 as seen inFigure 4, and in part on the apron clamp I29 as viewed in Figure 5.

This ring affords a chamber into which air under pressure is introducedand from which it is designed to escape into the space between the apronclamp I29 and the overlying portion of the top flange 25 of the spindle.In addition, the pressure of the air effectively prevents the escape ofany oil which may rise to the top of the pump ring 568. The top of theinner wall I41 is formed with a groove I49 which serves as a surfacebreak to impede the flow of capillary oil.

The outer wall Hi8 of the ring is formed with two openings communicatingwith passageways 1959 in the apron clamp I29 through which air is,admitted to the ring. In the present embodiment of the invention, thepassageways I50 are drilled in the apron clamp. The outer ends of thesepassageways are closed by removable plugs l5 l, while the under side ofthe clamp is formed with ports Hi2 communicating with the passagewaysvand formed so as to receive pipe connections. Ports I52 are connectedwith branch pipes I53 to a coupling I54 which receives air underpressure from a flexible pipe I55.

This combination seal of a vane pump on the spindle for driving orpumping the oil downwardly and of a circular air chamber effectivelyprevents water, grit, etc., passing downwardly around the spindle whereit would contaminate and ruin the bearings and also effectively preventsoil from seeping out from under the spindle flange where it mightinterfere with the surfac ing of the work.

As is known, a spherical surface will be im-.

parted to a lens blank when-the spindle supporting the blank rotatedsimultaneously with bodily movement of the spindle to and fro in acurved path, whereas a cylindrical surface will be im-.

parted to a lens blank when it is moved to and fro in a curved pathwithout being rotated.

From the foregoing, it will be perceived that simple and reliable meanshave been provided whereby lens blanks may be surfaced with extremeprecision by workers not necessarily having the knowledge and skillwhich has heretofore been required in doing work of this character.

What we claim is:

1. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a supporting member havingcurved guideways, lens blank holding means movable to and fro in saidguideways for moving the lens blank in a curved path. said meansincluding a body member, a spindle journaled in said body on which thelens blank is adapted to be mounted, hydraulically operated meansmounted in said member and movable therewith for rotating th spindle assaid means is moved to and fro, and passages in said body through whichthe fluid is conducted to and away from said hydraulic means.

2. Li a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a supporting elementhaving curved guideways, and lens blank holding means movable back andforth in said guideways to cause the lens blank to move in a curvedpath, said means comprising a body element supported in said guideways,a spindle journaled in said body on which a lens blank is adapted to benounted, and an oil gear motor having a plurality of gear wheels mountedin said body for rotating said spindle as the body moved back andjforth,one of said gear wheels being rigid with said spindle.

3. In a machine for surfacing lens blanks with a'relatively stationaryrotatable surfacing means, the combination of a supporting elementhaving curved guideways, and lens blank holding means movable back andforth in said guideways to cause the lens blank to move in a curvedpath, said means including a body element supported in said guideways, aspindle journaled in said body on which a lens blank is adapted to bemounted, an oil gear housed within said body for rotating thespindle asthe body is moved back and forth, said oil gear motor having a gearwheel rigid withthe spindle and a cooperating gear wheel having ductsfor the passage of oil to lubricate said spindle.

4. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, thecombination of a supporting element havingcurved guideways, and lens blank holding means movable back and forth insaid guideways to cause the lens blank to move in a curved path, saidmeans including a body element supported in said guideways, a spindlejournaled in said body on which a lens blank is adapted to be mounted,an oil gear motor mounted in said body for rotating the spindle as thebody is moved back and forth, said oil gear comprising a pair ofrotatable gear wheels, one of said gear wheels being rigid with thespindle and the other of said gear wheels having radial passagewayscommunicating with the inner portion of the space between the teeththereof through which oil is forced by the teeth of the other gear wheelto lubricate the'spindl when said wheels are rotated.

1 5'. In a machine for surfacing lens blanks with a relativelystationary rotatable surfacing means, the combination of a supportingelement having curved guideways, and lens blank holding means movableback and forth in said guideways to cause the lens blank to move in acurved path, said means including a body element supported in saidguideways, a spindle journaled in said body on which a lens blank isadapted to be mounted, an oil gear mounted in said body for rotating thespindle as the body is moved back and forth, said oil gear comprising apair of rotatable gear wheels one of which is rigid with the spindle, apin mounted in the body affording a rotatable mounting for the lastnamed gear wheel and said pin having passageways through which oil maypass from said motor to lubricate the spindle.

I 6. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a supporting elementhaving curved guideways, and lens blank holding means movable back andforth in said guideways to cause the lens blank to move in a curvedpath, said means including a body element supported in'said guideways, aspindle journaled in said body on which a lens blank is adapted to bemounted, and an oil gear motor mounted in said body for rotating thespindle as the body is moved back and forth, said oil gear comprising apair of gear wheels,'a pin within the body affording a pivotal mountingfor one of said gears and the other of said gears being rigid with thespindle, said first named gear wheel having a plurality of radialpassageways and said pin having a 1ongitudinally extending passagewaycommunicating with said radial passageway, the outer ends of said radialpassageways respectively terminating in the bottom wall of the spacesbetween the.

teeth of the said wheel wherebythe teeth of the cause the lens blank tomove in a curved path, 1

said means including a way block supported in said guideways, a spindlejournaled in said block on which a lens blank is adapted to be mounted,

and mechanism mounted on the under side of said way block housing thelower end of the spindle, said mechanism having an oil gear motor forrotating said spindle provided with a plurality of gear wheels one ofwhich is rigid with the spin-.-

dle, and a pin affording a mounting on which the second gear wheel isrotatable, said pin havinga longitudinal passageway for receiving oilfrom said second named wheel, and a groove on the under side of said wayblock for conducting oil from said longitudinal passageway to thespindle.

8. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of. a supporting elementhaving curved guideways, and lens blank holding means movable back andforth in said guideways to cause the lens blank to move in a curvedpath, said means comprising a body element slidably supported in saidguideways, a spindle rotatably mounted in said body element on which alens blank is adapted to be'mounted, an oil gear motor mounted withinsaid body element for rotating the spindle as the body moves back andforth, pipe connections pivotally mounted at the lower end of said bodyto which flexible conduits may be attached, and'means for supplyin oilfrom said motor to the spindle, the lower portion of said body housingthe lower end of said spindle and forming a sump for oil draining fromthe spindle.

9. In a, machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a supporting elementhaving curved guideways, and lens blank holding means movable back andforth in said guideways to cause the lens blank to move in a curvedpath, said means comprising a body element slidably supported in saidguideways, a spindle for holding a lens blank ro-tatably supported insaid body, a bearing in the body for said spindle, hydraulic means forrotating the spindle as the body moves to and fro, said hydraulic meansbeing movable with said body, said bearing having portions 'spaced fromcontiguous parts of the body forming spaces for receiving lubricantunder pressure and having passageways permitting lubricant to pass.

from said spaces to the inner face of said bearing.

10. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a supporting elementhaving curved" guideways, and lens blank holding means movable back andforth in said guideways to cause the lens blank to move in a curvedpath, said means comprising a body element provided with an openingslidably supported on'said guide ways, a bearing within said openinghaving portions spaced from adjacent walls of the opening, and an oilgear motor mounted within said body for rotating said spindle and forsupplying lubricant under pressure to said spaces between the bearingand the body, said bearing having passageways for conducting oil fromsaid spaces to the inner faceof the bearing.

1.1. In a machine for surfacing lens blanks with arelatively stationaryrotatable surfacing means, the combination of a supporting elementhaving curved guideways, a lens blank holding means movable back andforth in said guideways to cause the lens blank to move in a curvedpath, said means comprising a body element slidably supported on saidguideways, a lens blank supporting spindle rotatably mounted in saidbody, the axis of rotation of said spindle being disposed atsubstantially 90 to the axis of rotation of said surfacing means andhaving an exterior downwardly tapering surface, and a bearing in saidbody for the spindle, said bearing having a downw'ardly tapering innerface conforming to said tapering surface of the spindle and beingprovided with a circumferential oil receiving groove adjacent its lowerend, portions of the outer face of said bearing being spaced from saidbody to provide lubricant receiving spaces communicating with saidgroove, and means operable upon rotation of said spindle for supplyinglubricant under pressure to said groove.

12. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a supporting elementhaving curved guideways, a lens blank holding means movable back andforth in said guideways to cause the lens blank to move in a curvedpath, said means comprising a body element slidably supported on saidguideways, a lens blank supporting spindle rotatably mounted in saidbody having a downwardly tapering exterior surface, and a bearing forsaid spindle within the body, said bearing having a flange portionunderlying a portion of the spindle and a tubular portion having adownwardly tapering inner surface engaging said tapering surface of thespindle, the inner surface of said tapering portion and the uppersurface of said flange having grooves adapted to receive lubricant, saidgrooves in said flange terminating short of the periphery thereof, andmeans for supplying lubricant under presure to said grooves duringrotation of the spindle.

13. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a supporting elementhaving curved guideways, a lens blank holding means movable back andforth in said guideways to cause the lens blank to move in a curvedpath, said means comprising a body element slidably supported on saidguideways, a lens blank supporting spindle rotatably mounted in saidbody, a plurality of bearings mounted in said body for said spindle,each of said bearings having longitudinally extending lubricantreceiving grooves and the upper one of said bearings having a laterallyprojecting flange underlying a part of the spindle, said flange havingradially extending grooves terminating short of the periphery thereofcommunicating with the longitudinal grooves of said upper bearing, andmeans operable upon rotation of said spindle for supplying lubricantunder pressure to said grooves.

14. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a supportin element havingcurved guideways, a body member movable to and fro in said guideways, aspindle rotatably mounted in the body member, said spindle affording amounting for a lens blank and having a downwardly tapered peripheralsurface, a hearing in the body for said tapered surface of the spindle,said body having an enlarged portion forming a housing for the lower endof the spindle, and removable means within said housing for locking saidspindle against upward movement.

15. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a supporting elementhaving curved guideways, a body member movable to and fro in saidguide'ways, a rotatable spindle journaled in said body affording amounting for a lens blank, said spindle having a shouldered portion anda downwardly tapering peripheral surface, a bearing in said bodysurrounding said peripheral surface and underlying a portion of saidshouldered portion of the spindle, and means removably mounted on thelower end of the spindle for locking the spindle against upward movementwith respect to the body.

16. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a beam member havingupstanding wall portions respectively provided with curved recesses ontheir inner faces, members removably connected to said wall portions andoverlying the recesses thereof so as to form curved grooves in the innerfaces of said walls, and a lens blank holding means movable back andforth in said guideways to cause a lens blank to move in a curved path.

17. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a beam having upstandingwall portions respectively provided adjacent their upper edges withcurved recesses, members removably connected to said wall portionsoverlying said recesses to form curved grooves in the inner faces ofsaid walls, and lens holding means between said walls movable to and frolongitudinally thereof, and ribs removably secured to opposite sides ofsaid lens holding means slidably mounted Within said grooves wherebysaid means is caused to travel in a curved path when moved to and fro.

18. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a supporting elementhaving curved guideways, a body movable back and forth in said guidewayshaving a rotatable spindle on which a lens blank is adapted to bemounted, apron means secured to said body member adjacent the upper endof the spindle and extending in opposite directions therefrom forpreventing loose material incident to the surfacing from dropping on tothe top of the body.

19. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a supporting elementhaving surved guideways, a body movable back and forth in said guidewayshaving a rotatable spindle on which a lens blank is adapted to bemounted, a flexible apron above said body having an opening intermediateits ends through which said spindle extends, said apron being secured toand movable with said body, spaced means respectively connected toopposite ends of the apron for maintaining the apron in ten sion as thebody moves to and fro.

20. In a machine for surfacing lens blanks with a relatively stationaryrotatable surfacing means, the combination of a supporting elementhaving curved guideways, a body movable back and forth in saidguide-ways having a rotatable spindle on which a lens blank adapted tobe mounted, and an apron above said body connected thereto and having anopening interme-

